With the continuous development of the display technology, due to the advantages of small size, low power consumption, no radiation and the like, Thin Film Transistor Liquid Crystal Displays (TFT-LCD, for short) dominate in the panel display field. After a liquid crystal display panel is well manufactured, it is required to perform quality inspection, and among others, bright spot detection is an important one of the quality inspection items.
An existing method for detecting a bright spot of a liquid crystal display panel is as follows: cyclically scanning gate lines of the liquid crystal display panel, and simultaneously outputting low level signals by data lines. Under normal circumstances, the liquid crystal display panel will display a black image. If a TFT of a certain pixel breaks down, for example, a pixel electrode is in short circuit with a gate, a high level signal will be input to the pixel electrode and the corresponding pixel will be displayed as a bright spot. In this way, the bright spot is detected.
During the implementation of the present invention, the inventor(s) found that there are at least the following problems in the prior art. As shown in FIG. 1, many bright spot defects at present are mostly caused by the fact that a pixel electrode 2 is in short circuit with a data line 3 due to the presence of foreign matters 1 (or film layer residuals) in a pixel region and is thus out of control of a TFT 4. For example, for an Advanced super Dimension Switch (ADS, for short) type liquid crystal display panel, particularly in the case that its driving mode is a row inversion driving mode of which the Gate driver On Array (GOA, for short) technology is representative, the above problem is particularly acute. Specifically, by using the existing method for detecting a bright spot of a liquid crystal display panel, if the data line 3 outputs a low level signal at the same time of scanning gate lines 5, the low level signal will be input to the pixel electrode on the liquid crystal display panel, wherein the low level signal will also be input to the pixel electrode 2 in short circuit with the data line 3, so that the pixel where the pixel electrode 2 in short circuit with the data line 3 is located will not be displayed as a bright spot. Therefore, the existing method for detecting a bright spot of a liquid crystal display panel can not detect a bright spot caused by the short circuit of a pixel electrode with a data line and is likely to result in missed detection in the bright spot detection process.